EN/ BS Plate Flange
- Pressure range: PN6-PN40 and Class 150/300
- Standard: EN 1092-1, BS 4504
- Nominal diameter: DN10 to DN2000 (1/2“-80”)
- Sealing surface type: RF, FF
- Material: carbon steel, stainless steel, alloy steel
- Size tolerance:
Outer diameter: ±1.5mm (DN≤300)
Bolt hole center circle diameter: ±0.5mm
Flange thickness: +2mm/-1mm
We have been manufacturing and selling pipe fittings for more than 20 years, selling low prices and producing high quality pipe fittings are our obvious advantages, welcome to inquire.
EN/BS Plate Flange, this neckless supported flat flange conforms to EN 1092-1 and BS 4504. It is welded on both sides to connect directly to the end of the pipeline, with convex (RF) or flat (FF) sealing design, suitable for metal-wound gaskets or rubber gaskets, the material covers carbon steel, stainless steel and alloy steel, with low manufacturing cost, easy installation and other characteristics, is widely used in the sealing and connecting of low-pressure system pipelines for water treatment, HVAC and chemical industry.
EN/ BS Plate Flange Specification
Seal Forms: Flat (FF) without flange sealing surface, suitable for low pressure scenarios; Raised (RF) with annular tabs to enhance sealing reliability.
Standard system: EN 1092-1 belongs to the European PN series standard, while BS 4504 is the traditional British standard, which has been replaced by EN 1092-2.
Cutting process: plasma cutting: for flange blanks with thickness >50mm, bevel angle needs to be controlled 35°±2°; laser cutting: preferred for thin plates (<20mm), with dimensional accuracy up to ±0.1mm.
Temperature: EN 1092-1 reference temperature 120°C
EN/ BS Plate Flange Advantages
| Advantages | Limitations |
| Low Cost: Simple structure, reduced material consumption, 30-50% cheaper than necked flanges (WN) | Limited Pressure Resistance: Suitable only for systems ≤PN40; high-pressure scenarios require welding neck flanges (WN) |
| Easy Installation: Double-sided welding without groove preparation, improving construction efficiency | Poor Vibration Resistance: No neck support, prone to leakage under frequent vibration or thermal cycling |
| Flexible Maintenance: Disassembly requires only bolt removal, avoiding pipe cutting | High Precision Required: Welding surface flatness must be ≤0.1mm/m to prevent sealing failure |
EN / BS Plate Flange Size Chart
EN/ BS Plate Flange Advantages Application
- Water Treatment and HVAC
Used for low-pressure water supply pipes (≤PN10), such as municipal water supply, and sewage treatment plant pumping station connections, relying on its low cost and corrosion resistance (carbon steel/stainless steel material).
Suitable for HVAC circulatory systems, quick installation through double-sided welding, reducing construction cycles.
- Chemical and Energy Sector
For low-pressure chemical piping (PN16), such as acid and alkali media transportation (with 316L stainless steel).
For low-pressure steam systems (≤16bar), with metal-wound gaskets (EN 1514-2) to achieve a stable seal.
- Frequent disassembly and maintenance
Ship maintenance, temporary piping connections, often used in combination with loose flanges (PJ/RJ), to avoid repeated welding damage to the pipeline.
Equipment maintenance ports, instrument interfaces and other parts that need to be dismantled on a regular basis, utilize the flexibility of its bolt connection to simplify the maintenance process.
- Non-pressure-bearing closure and end sealing
The end of the pipeline or equipment port adopts flange cover (BL) sealing to prevent media leakage or foreign matter from entering.
It is suitable for non-pressurized scenarios such as ventilation ducts, tank manhole covers, etc., and meets the requirements of lightweight design.